1. Field of the Invention
This invention relates generally to methods of preparing soft tissue, such as breasts, for augmentation and, relatedly, to methods of enhancing fat and adipocyte derived stem cells grafting results, and augmenting and restoring soft tissue by autologous fat and adipocyte derived stem cell grafting.
2. Related Art
There are numerous instances where persons desire augmentation of soft tissue such as their breasts. Other examples of soft tissue augmentation opportunities include the face, the buttocks, depressed scar contours, tissue atrophy related to aging, scarring, radiation or disease, or any body deformity or area that is desirably augmented. Another such instance is for the augmentation or the restoration of one or both breasts subjected to a partial or total mastectomy, a biopsy, or other disfiguring events in order to restore physiological symmetry and psychological well-being. Yet other instances are for correction of natural abnormalities such as scarring and dimpling. Still other instances are for augmentation of the breasts to improve cosmetics and self-esteem.
Liposuctioned fat is known to be rich in stem cells that have the ability to restore and reconstruct various soft tissue defects in response to local differentiation clues from the recipient site. This invention also relates to providing for improved survival of larger graft volumes in a given recipient site.
Prosthetic implants have been developed for insertion below the skin. However, the severity of the potential complications including scarring, implant rupture, capsular contracture, necrosis and implant migration as well as the recent adverse publicity thereof have significantly reduced the desirability of these implants. While scientific evidence is not conclusive, there is some indication that breast implants might contribute to secondary diseases. Thus, there is a societal need for other means to obtain breast augmentation.
Breast augmentation by use of fat grafts was experimentally explored in the past but has not gained widespread acceptance. First, the larger blocks of grafts used then displayed poor survival. Secondly, the failed grafts sometimes produce stellate irregular nodules with calcifications. These nodules, which were often palpable, were occasionally indistinguishable from cancer with the breast imaging technology available at that time. For these reasons certain medical societies and associations advocated a ban on fat grafting to the breast. Consequently, the practice of fat grafting to the breast was contraindicated and not pursued.
Subsequently, digital mammography, high-resolution ultrasound, Magnetic Resonance Imaging (MRI) and its associated absorption curve and fat suppression views have revolutionized breast imaging. As a result, radiologists now have the imaging technology that enables them to differentiate with reasonable certainty a neoplastic process from the fat necrosis commonly left behind following reduction mammoplasties, the now accepted SAL (Suction Assisted Lipectomy) breast reduction methods, breast biopsies, and even non-surgery related every day breast trauma. It is consequently evident that concerns associated with distinguishing areas of fat necrosis resulting from fat grafting to the breast from areas of neoplasia have now been essentially obviated by advances in imaging technology. With these advances, fat grafting may now again be considered for this application.
Described herein is a new method of preparing soft tissue for augmentation, including preferably the breasts, for enhancing fat grafting results in soft tissue, and augmenting soft tissue by use of autologous fat grafts. This may preferably be as general method for preparing a soft tissue recipient to successfully accept the survival of larger graft volumes, whether these are fat droplets, stem cells or other dispersed live cell injections. This method does not suffer from the defects of the previously attempted methods of fat grafting to the breast in that it results in high rates of larger volume graft survival and marked reductions of graft necrosis and calcification. This method is distinguished from previously disclosed methods by, inter alia, the use of devices that exert a distractive force on the breast to increase the volume of the recipient space, increase its vascularity and generate a fertile extracellular fluid matrix which prepares the soft tissue site for improved graft survival. This technique enhances the results in conjunction with improved techniques of autologous fat harvesting, processing and grafting and other techniques of tissue culture.
Soft tissue grafting, augmentation and restoration of tissue loss by dispersion of small micro-grafts is three dimensional grafting which requires novel concepts. Just as in two dimensional grafting, one cannot apply more grafts than the surface area of the defect, and stacking more grafts is counterproductive. In 3D grafting, even with the best and most even dispersion of the finest graft droplets, one cannot graft more than the volume of the recipient site defect (see drawing figure). It follows therefore that expansion, even temporarily, of the recipient space by external distraction would increase its volume and create room for more grafts to survive. In addition, it is well known that tissue expansion is angiogenic, (increases the vascularity) and that improved vascularity leads to more successful engraftment. Furthermore, the increased extracellular fluid matrix of the expanded tissue is rich in growth factors and other agents known to render the site more fertile for graft survival.